U.S. criminal investigators are re-examining cases against 103 scientists at the National Institutes of Health, most of whom were cleared in previous ethics probes or received light reprimands or warnings over conflict-of-interest complaints.

Following strong criticism from Congress, the investigative arm of the Department of Health and Human Services also has begun a review of conflict-of-interest policies at the NIH, one of the world’s premier medical research centers.

The review affects not only government scientists but also the way that NIH oversees grant recipients who perform research at universities or other non-federal institutions.

The decision by the inspector general for the Health and Human Services Department to re-examine cases against 103 employees at the NIH suggests the earlier investigations were mishandled, said Rep. John Dingell, D-Mich., chairman of the House Energy and Commerce Committee.

“The inspector general is taking a much-needed closer look,” Dingell said. “Even if only a few of those cases result in criminal prosecution, it is clear that NIH bungled the investigation the first time around.”

A spokesman for the inspector general declined to discuss new case reviews. The NIH also declined to comment.

The inspector general, Daniel Levinson, disclosed the re-examinations and broader policy review in a letter to Rep. Joe Barton of Texas, the top Republican on the House Energy and Commerce Committee.

The earlier ethics reviews led to full-blown investigations by the inspector general in two cases. NIH’s internal probe found no violations in more than half of the cases overall.

However, Levinson’s team now has concluded that “potential conflict-of-interest concerns existed with 103 NIH employees.” Its investigators and attorneys “are presently examining these cases to determine whether investigation is warranted,” according to Levinson’s letter.

NIH had referred the 10 most serious cases to the inspector general, who investigated two. Those cases led to one misdemeanor conflict of interest plea in federal court by an Alzheimer’s researcher who was sentenced to community service and forfeiture of $300,000.

NIH’s toughest sanction was a 45-day suspension for a person who failed to seek approval for his outside work and failed to report outside income of $474,730. A handful of others received suspensions of a few days for similar infractions while still others received written or oral warnings.

Lawmakers in recent years have complained that NIH is lax in policing of scientists earning outside money. NIH cracked down in 2005 with a new policy that bans employees from accepting consulting fees, stock or stock options from drug or biotech companies.

Under previous rules, the researchers were allowed to earn outside income but were required to obtain prior approval from NIH. They also could not accept pay for work that overlapped their government projects. The 103 cases in question occurred under those rules, going back to 1999.

“It’s good that they have now decided to engage in a full-scale examination of the NIH’s ethics operations and program,” Barton said.

Ethics advocates said they hoped new reviews would reveal any conflicts that might have tainted past medical research.

“Who knows how much damage these conflicts of interest have done to the NIH mission of protecting the public’s health?” said Ned Feder, a former NIH scientist who works now with the private Project on Government Oversight. “A review of the facts and the policies is long overdue.”

Current rules covering NIH employees do not apply to the outside researchers who receive NIH grants. Grant rules stipulate that outside institutions enforce their own conflict-of-interest policies and voluntarily report any conflicts.

NIH looked into the potential conflicts after congressional investigators reported nearly three years ago that many government researchers were making thousands of dollars from drug and biotech companies but failing to disclose that outside income as required.

At a hearing last September, lawmakers criticized NIH for light penalties meted out and criticized the inspector general for letting NIH’s internal probes be the final word. Most of the cases involved failing to ask permission or follow procedures for doing outside work.

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